There are many and various types of mechanical arm mechanisms in the art and conventionally each is specific to a particular motion problem. Many of these comprise parallel arms or links which must remain parallel throughout the motion excursion while others comprise link-and-cam arrangements which compensate for possible interference between the links as they are moved from one position to an alternative position. Most of these prior art mechanisms must function in a limited way to move a table or like-type board surface from a first initial position to a second alternative user position and the same configuration of arm mechanism may not be reconfigured to other applications which effect a change in both of the initial and alternative user positions.
A typical example of a prior art arm mechanism is U.S. Pat. No. 596,931 issued to F Yunck which shows support arms pivotally attached to a floor to support a restaurant stool which can be moved from a horizontal user position to a vertical stored position next to a counter. This device is limited in its range of movement for its specific purpose and provides for no adjustability or for supporting any other kinds of equipment or multiple user surfaces.
The present invention is a further development of my previously mentioned copending application 08/574,293 and provides additional versatility for handling additional types of user equipment which need to be moved from a stored to a user position. The methods of establishing the positions of arm members and pivot points as described in my above mentioned prior application are equally applicable to this application. For brevity, all the prior description will not be repeated herein, however the methods and apparatus shown and disclosed therein are incorporated in their entirety in this application.